MRCP-1033

MRCP-1033

A 74 year old man presents with 12 kg weight loss and persistent back pain that is unrelated to activity for the past several months. Laboratory findings show : WCC: 6.7 x 109/l (5.4 neutrophils, 1.2 lymphocytes and 0.2 monocytes), Haemoglobin: 11.2 g/dL, Haematocrit: 33.3%, MCV: 88 fl, Platelet count: 89 x 109/l. The biochemistry shows: sodium 144 mmol/L, potassium 4.5 mmol/L, chloride 100 mmol/L, bicarbonate 26 mmol/L, urea 14 mmol/L, creatinine 90 μmol/L, glucose of 5.4 mmol/l. A CT scan of the spine reveals scattered 0.4 to 1.2 cm bright lesions in the vertebral bodies. Which of the following additional laboratory test findings is he most likely to have?